The Division of AIDS, NIAID, NIH intends to award a contract for a Virology Quality Assurance Program to ensure the integrity and comparability of virologic laboratory data obtained from multi-center AIDS clinical trials sponsored by the Division of AIDS. To that end, the Contractor will obtain, characterize and store quality control materials, such as whole blood from HIV positive and negative donors, viral lysates with varying concentrations of HIV p24 antigen, HIV proviral DNA copy number standards, and other HIV and its associated co-pathogens viral probes and reagents. These materials will be shipped periodically to 60 - lOO designated laboratories for the purpose of monitoring virologic assay performance through a program of proficiency testing and real-time assay validation. In addition, the Contractor will facilitate the field testing of virologic assays prior to their implementation in clinical trials; evaluate and compare assay methodologies and commercial assay kits/reagents; and apply existing or novel statistical models for evaluation, interpretation and display of virologic assay test results. These activities will be supported by a computerized database and analysis systems.